Electrical devices for verifying the authenticity of a circular plate body such as a coin using changes in magnetic flux generated by a coil are known in the prior art. For example, there is a coin sorting device described in the specification of Japanese patent application no. 7-46088. This device has a passage to pass one coin with coils arranged at each side of the passage and connected in series. Two other coil means are arranged at each side of the passage and are connected in parallel. Means are provided to oscillate, at a low frequency, the circuits energizing the coils which are serially connected and to oscillate the other coils at a high frequency. A problem with this system is that the inserted coin must move a base in the passage which represents a standard surface. This alignment requirement reduces the speed and accuracy at which the authenticity of the coin or token can be tested.
It is an object of the present invention to overcome the problems noted above with the prior art. Specifically, it is an object of the present invention to improve the speed at which the authenticity of the coin or token can be tested and to devise a simple structure which allows the coin to fall or roll naturally.